Geared turbofan engines utilize a gas powered turbine engine to drive rotation of a fan through a gearing system. The fan drives air along a bypass flow path in a bypass duct defined within a nacelle, while a compressor section drives air along a core flow path for compression and communication into a combustor section with subsequent expansion through a turbine section. The compression section draws in and compresses air, the combustor section mixes compressed air with a fuel and ignites the mixture, and the combustion products are expanded across the turbine section. This expansion across the turbine section drives the turbine to rotate and communicate this rotation to the compressor section via at least one shaft. The rotation of the shaft is translated through the gearing system to the fan, which is positioned forward of the compressor section.
When an aircraft with a geared turbofan engine is in a non-operational mode, such as when the aircraft is parked at an airfield, some of the gas turbine engine components are subject to rotation. For example, crosswinds entering the geared turbofan can drive rotation of the fan in either a clockwise or counterclockwise direction, dependent on the direction of the wind. This rotation is referred to as windmilling. Rotation of the fan, in turn, is translated to the shaft through the gearing system. In some geared turbofans, one or more components within the engine require active lubrication while the engine is rotating in order to prevent damage or deterioration to the engine systems.